With a budget of nearly half-a-billion pounds a year, they will lead the fight against the estimated 37,000 criminals involved in serious and organised crime that hits the UK.

More than 4,000 NCA officers will tackle crime under four commands, organised crime, economic crime, border policing and child exploitation and online protection, alongside a National Cyber Crime Unit.

He said: “To be clear, there will be no one beyond the reach of law enforcement or beyond the reach of the NCA.

“Those people involved in the most horrible activities can expect the most comprehensive and robust response.”

The launch of the NCA spells the end of the Serious Organised Crime Agency (Soca) which set up in 2006, as it is to be absorbed into the new organisation.

Proposals for the new agency were first unveiled by Home Secretary Theresa May in July 2010 as part of a broader shake-up of the policing landscape.

Announcing the new US-style agency, Mrs May said it would have a sweeping new power to step in to directly task and co-ordinate police forces in a bid to tackle organised crime and secure the UK’s borders.

Too many of the near-6,000 organised crime gangs in the UK were escaping justice and a tough new approach was needed, she said.

The NCA has an annual budget of £463m for resources and £31m for capital.

It will run the country’s first national intelligence hub, place investigators at UK ports to tackle border crime such as human trafficking and will track down child-sex abusers online.

It will also place around 120 officers overseas in 40 different countries.

Mr Bristow, a former chief constable of Warwickshire Police, said unlike Soca, the NCA would not operate as a covert organisation and wants to be recognised by the public.

Some of its officers will wear jackets and caps emblazoned with NCA when on operations.

“We’re going to be visible,” he said.

“We want the public to know who we are, what we do, what we’re delivering, to understand the serious and organised crime threat that effects every neighbourhood and every citizen throughout the UK.”

He added: “Frankly, we want the criminals to know who we are, because we want them to fear our attention.”

The NCA will also be recruiting special officers.

These will be volunteers like special constables in police forces with knowledge of the cyber or the financial sector.

Home Secretary Theresa May said: “I want to make Britain a hostile environment for serious and organised criminals.”